Connect TP-Link router to Internet

I have an old TP-Link router which is used as a Test network For VM's. The Network on the TP-Link has a different subnet mask ( to my main network (

is they a way to give internet access to the TP-Link router.

Surely in the router there's the option to change the IP address of the device and the subnet mask. Go from there and you'll get everything working.

I cannot set a subnet mask of on my router since it’s rubbish.

The TP-Link (test network) is simulating a network with a Subnet of which means the servers cannot be moved to my main network ( /24 ) .